- Composition and Overview of WLQ20/110Jetting Machine
WLQ jetting machine is composed of high pressure pump, motor, coupling, tri-star starter control box, relief valves and safety valves, etc. It is a necessary maintenance equipment to conduct industrial cleaning on the rusty and dirty surface of objects. This machine adopts separated head of cylinder liner (national patent, patent No. ZL 95 241067.2), and is characterized by high pressure, sufficient flow, smooth and reliable running and flexible operation, as well as easy maintenance, which is "a shining star" among similar products.
- Hydraulic system
The entire system consists of high pressure pump, relief valve, safety valve, foot valve, water gun, enter-return flexible hose, water tank and distribution box. During working hours, fresh water injects into water tank through flexible hose, and then enters the low pressure chamber of pump fluid end via imbibing filter, imbibing flexible hose and imbibing stop valve. High pressure water is transported to workplaces after several segments of high pressure hose. There are two kinds of working conditions:
Condition 1: It is controlled by the foot valve (water gun is not used). Such condition is generally used for the cleaning of pipe walls. Foot valve is used to control the switch.
Condition 2: It is controlled by water gun with switches (foot valve is not used). Such condition is generally used for the cleaning of rusty and dirty surface, as well as general washing. Water gun is used to control the switch.
A relief valve is deployed at the high-pressure outlet of the pump, to adjust the actual operating pressure. Excessive water shall return to water tank via the overflow port at relief valve and liquid return pipe. Pump safety valve is also deployed, which can be opened automatically when the pumping pressure is increased due to unexpected factors, in order to protect the pump and motor against shockproof pressure gauge and display the working pressure.
3. Structural description
3.1 Jetting machine
Jetting machine is a device that can convert drives of electric motor or diesel engine to high pressure water fluid pressure energy. WLQ clean water pump belongs to horizontal three-plunger reciprocating high-pressure pump.
Structures of the pump please see the diagram. It mainly consists of housing assembly, pump head assembly, coupling, bottom bracket, and electric motor or diesel engine.
Three-phase four-pole AC motor or diesel engine can drive the rotation of three throw crank shaft via coupling and gear reducer. It can also act on the connecting rod and slide block mechanism, make slide block reciprocates in the box slipway, plunger is also driven to do reciprocating movement. When the plunger is retracted, vacuum is formed in hydraulic chamber. At this time, water self-cleaning tank enters the hydraulic chamber via fluid flexible hose, dispensing tube and top open suction valve. When the plunger is moving forward, suction valve closes off. The water is pressurized, the drain valve is opened, and being output outward through high pressure fluid collection block.
Tank components: Tank is the bearing body of pump, which is made of cast iron with high strength. One of its sides is set with gear box. A pair of gears inside the box is made of high quality structural alloy steel, with hard-tooth-surface of high precision after grinding and special heat treatment. It has the features of smooth rotation, low noise and excellent wear resistance. The crankshaft is made of alloy steel, and crank surface hardness with high strength can be achieved after special heat treatment. Connecting rod big end is lined with high tin aluminum bearing bush, with excellent wear resistance. Connecting rod big end moves in the crankcase.
Pump head assembly: Details of pump head assembly please see the diagram. Three separated cylinder liners have replaced the traditional block pump heads and three high-pressure steel sleeves. Such structure can fundamentally solve the easily-damage connection between primary structural pump head and high pressure steel jacket, which might cause pump head cracking if not repaired. Three separated heads have greatly simplified the maintenance disassembly, and reduced labor intensity. Piston alloy surface is treated with special alloy, in order to enhance the primary hardness, wear resistance and corrosion resistance. Plunger and slider are connected by pressure block, semi-toroidal, nut and locking screw. During the usage process, changes in the axial gap and screw loose should be paid attention to. Plunger is sealed with imported packing rectangular ring, with longer seal life. None cross-hole assembly structure (see diagram) is used on the combination valve, which can realize flexible startup, reliable sealing, and durable life.
3.2 Relief valve
Function:
Relief valve is an important element of the hydraulic system, whose role is to ensure the operation of working pipeline under preset pressure. The total flow of the pump is automatically divided into two parts when passing through the relief valve, one is used by water gun or a variety of accessories; the excessive flow shall return to the tank, and maintain a constant pressure.
Structure and operation principle:
Pilot operated compound-relief valve is used. It composed of pilot valve and main valve.
Pilot valve element is connected with the back liquid chamber of main valve via the center hole, also connects to P port in pressure chamber via two choke plug holes inside the main valve element chamber. In this way, pipeline pressure changes of working pipeline can reflect to the pilot valve element. When adjusting the pilot valve spring, pressure between choke plug and pilot valve will increase, resulting in pressure in the working chamber. Adjust the working pressure continuously until suitable and stable working pressure is obtained. Under the circumstance there is no pressure between choke plug and pilot valve, the working pressure shall be zero.
3.3 Safety valve
The role of safety valve is to conduct overload protection on pump station, i.e. the pressure relief can be started automatically when the pump pressure is increased due to unexpected reasons.
Structure is shown in the diagram. One end of the valve is connected with high pressure chamber, when the pressure exceeds a predetermined value, hydraulic force shall fight against the spring force to open the valve and release pressure. Generally, the pressure of safe valve shall be adjusted to 110% of the working pressure. The nut is fastened after the adjustment to prevent loosening.
No matter consider from the safe operation of pump station, or from the safety concerns of workers, the set up of safe valve should be taken into account.
3.The technical parameters
| The technical parameters and pricing of WLQ20/110 Jetting Machine | |
| Nominal Pressure | 110MPa |
| Nominal Flow | 20L/min |
| Motor Power | 45KW |
| Motor Speed | 980R/min |
| Power Supply Voltage | 380V/3P |
| Working Fluid | Sea Water |
| Water Pressure | ≥0 MPa |
| Plunger Diameter | 20mm |
| Maximum Water Temperature | 45ºC |
| Crankshaft Speed | 370R/min |
| Plunger Travel | 70mm |
| Total Weight | About 1380kg |
| Shape Dimensions | 2230×1210×1100mm |
| Safety Valve Factory Pressure | 120MPa(110% of the rated pressure) |
| Overflow Vavle Factory Pressure | Rated Pressure 0-110MPa |